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"If a cone be cut by a plane, parallel to the base, so as to form two parts, the lower part is called the frustum of the cone." — Hallock, 1905

Cone

"If a cone be cut by a plane, parallel to the base, so as to form two parts, the lower part is called…

"If a pyramid be cut by a plane, parallel to the base, so as to form two parts, the lower part is called the frustum of the pyramid." — Hallock, 1905

Pyramid

"If a pyramid be cut by a plane, parallel to the base, so as to form two parts, the lower part is called…